A uniform narrow bar, resting on ice, is given a transverse horizontal impulse at one end as shown. The center of mass of the bar COM will then:
A) remain at rest
B) move in a circle
C) move in a straight line
D) move in a parabola
E) move along some other curve

Question

A uniform narrow bar, resting on ice, is given a transverse horizontal impulse  at one end as shown. The center of mass of the bar COM will then: 
A) remain at rest 
B) move in a circle 
C) move in a straight line 
D) move in a parabola 
E) move along some other curve

Quizplus · Accepted Answer

The impulse given to the bar will result in the bar experiencing a net force. The bar will accelerate in the direction of the force, causing its center of mass to move in a straight line. Since no other forces are acting on the bar, it will continue to move in a straight line at a constant velocity (assuming no friction with the ice). Therefore, Choice C is the best answer.

A Uniform Narrow Bar, Resting on Ice, Is Given a Transverse